Stair elevator



April 6, 1954 Filed May 25, 1946 l. c. THOMPSON 2,674,347

STAIR ELEVATOR 3 SheetsSheet l 57 6 1 9' j/rt INVENTOR. [rm/1gQT/mmnsan.

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I. C. THOMPSON STAIR ELEVATOR April 6, 1954 3 Sheets-Sheet 2 Filed May25, 1946 I. C. THOMPSON STAIR ELEVATOR April 6, 1954 5 Sheets-Sheet 3Filed May 25, 1946 Patented Apr. 6, 1954 STAIR ELEVATOR Irving 0.Thompson, Bay City, Mich., assignor, by mesne assignments, to Lloyd C.Schwartz,

Bay City, Mich.

Application May 25, 1946, Serial No. 672,179 9 Claims. (01. 187-42) Thisinvention relates to stair elevators such as installed in stairways forelevating heavy or light materials from the basement to the first floor,or from one floor to another.

It is conventional practice, where conditions require the shifting ofcommodities and/or materials from one floor to another to utilize avertically movable elevator mechanism, and special provision must bemade for such installation. This entails elevator shafts and wells,together with a cage or platform and the necessary forms of protectivemeans or devices.

Where installation is made in a building already constructed, remodelingof the interior i necessary, and furthermore, the considerable spaceoccupied by the shaft and well is unavailable for other purposes.

One of the salient objects of the invention is to design an apparatus ofthe character described which may be installed in a stairway passage ofpractically any type, either in newly constructed or old buildings, andwhich will convey packages or materials of any nature, either up ordown, as circumstances may require.

Another object of the invention is to design a stairway elevator whichcan be installed over the stairway and by means of which merchandise ofany nature may be raised or lowered, yet leaving the stairway properopen for use in the conventional manner.

A further object is to design a practical and substantial apparatusprovided with automatic braking apparatus and which will operate in amanner to eliminate any possibility of damag to load, or injury topersons carried thereby or engaged in the operation thereof.

A still further object is to provide a stairway elevator of simpleconstruction, which is composed of few parts, whereby the cost ofmanufacture and installation is reduced to a minimum Still a furtherobject is to provide equalizing means for equalizing the individualoperating cables as the device is operated.

A further object still is to design simple and practical means fortripping the switch and out off the power when the elevator platform hasreached the limit of its upward travel.

With the above and other objects in view, the present invention consistsin the combination and arrangement of parts, hereinafter more fullydescribed, illustrated in the accompanying drawings, and moreparticularly pointed out in the appended claims, it being understoodthat changes may be made in the form, size, proportion, and 'minordetails of construction, without departing from the spirit, orsacrificing any of the advantages of the invention.

In the drawings:

Fig. l is a plan view showing my stairway elevator installed over astairway.

Fig. 2 ,is a side-elevational view thereof.

Fig. 3 is a rear-elevational view showing the cable equalizing means,the stairway being omitted.

Fig. 4 is an enlarged, detail, side-elevational view of the cableequalizing means.

Fig. 5 is an enlarged plan view thereof.

Fig. 6 is a side-elevational View illustrating the elevator safetymechanism.

Fig. 7 is a top, plan view thereof.

Fig. 8 is a transverse sectional view taken onv the line 8-8 of Fig. 6.

Fig. 9 is an enlarged, fragmentary, side-elevational View of theelevator showing the trip mechanism.

Fig. 10 is a view similar to Fig. 9 showing the mechanism in trippedposition.

Fig. 11 is a fragmentary, plan view of the mechanism illustrated in Fig.10.

Fig. 12 is a fragmentary, part-sectional plan view of the tripmechanism, etc.

Fig. 13 is an enlarged, side-elevational view of the pit and platform.

Fig. 14 is a fragmentary, part-sectional, sideelevational detail viewshowing the cable anchoring means.

Referring now more specifically to the drawings in which I have shownone embodiment of my invention. The numeral It indicates a floor with astairway S leading from a floor it to an upper floor ll located apredetermined distance above it.

A relatively small pit P is provided in the floor It as shown and theelevator platform l2 forms a cover for said pit when in lowered positionas shown in Figs. 1 and 2 of the drawings.

The elevator is designed so that it can be installed directly over astairway so that the stairway may be used in the conventional mannerwhen the elevator is not in operation, said elevator comprisingspaced-apart side rails 53 and It, the lower ends of which are anchoredin the pit, the upper ends being secured to vertically disposedstandards it provided on the floor ll, these standards also forming amounting for the sheaves I? which are revolvably journaled therein.

The side rails l3 and M are substantially channel shaped in crosssection '(see Fig. 3), excepting that the lower section is closed bymeans of an upwardly projecting web l8 as shown.

Spaced-apart sheaves is are journaled in brackets 20 that are secured tothe floor H, and links 2! are pivotally secured to the brackets 20 bymeans or" pins 22, sheaves 23 being journaled on pins 2 3 provided onthe lower ends of the links 2|, and a horizontally disposed equalizingbar E connects the lower ends of the links 2| as shown.

A winch W is located on the floor Ill below the equalizing bar andincludes winding drums D as shown, said drums being driven from a motorM, and a brake C is connected to the motor for application when the mtorstops, and while in the present instance I have shown an electric motoras the source of power supply, it will be understood that any desiredsource of power may be utilized.

Pairs of depending brackets 25 and 28 respectively are formed on thebottom face of the platform [2, and legs 2? are pivotally connected tothe brackets 25, offset rollers 28 being journaled on the lower ends ofthe links, and are mounted for travel in the side rails l3 and 14. Links29 are pivotally connected to the brackets 26, each link being slottedas at 39, and a bolt 3| serves to secure the link to the leg El so thatthe legs can be adjusted to maintain the platform level.

Grooved rollers 32 are provided on the front end of the platform, theserollers being mounted for travel in the side rails l3 and M and arejournaled on pins 33 mounted in brackets 34 as usual, and a trippingmechanism S (see Figs. 9 and is mounted thereon and is actuated in amanner to be presently described.

An automatic brake mechanism B is mounted in the side rails l3 and M andcomprises spacedapart links 35, one end of these links being pivotallyconnected to the axle pin 36 on which the grooved sheave 37 is journaledand over which the hoist cable H is trained.

Slides 38 are mounted on the side rails as shown, and include anoverlying section 3% that rides on the upper edge of the rail. An arm 39forms a part of the brake mechanism B, the free end of said arm beingconnected to the leg 2'4 by means of the pin 45!. A pin 4| is mounted onthe slide 38, and a brake element F is rockably mounted thereon, saidelement being formed with a leg 42, and pins 53 serve to pivotallyconnect said legs to the links 35 at a point intermediate their length,said element being formed with a cam-shaped head, the rim of which isformed with fine, closely spaced teeth 44 to provide sharp biting actionwith the side rails when in engaged position.

A coil spring 45 is anchored to the ends of the links 35 and to thelever 39 at the point 38, so that should one of the cables break or themechanism otherwise disengage to release the platform, the brake elementF will engage the side rails and hold the platform in position thereon.

The lift cables H operate in the side rails l3 and i4, one end of eachcable being connected to an eye bolt 48 provided on the standard it,thence the cable leads downwardly beneath the grooved roller 32, thencearound the grooved sheaves 31, and thence upwardly and over the sheavesH, and thence to the winch.

Limit switches L are provided at the top and bottom of the side railsfor cutting off the power when the platform reaches the top and bottomof the rails. A plate 49 is pivotally connected to the angle 5% whichforms a part of the platform i2, and a roller 5| is journaled on a pin52 provided on the plate 49, a spring 53 being anchored to the plate 59at the point 54, and to the plate 55 which is welded on the shaft 56,said plate overlying the respective floors when the elevator is inposition for loading or unloading.

Raised brackets ii? are mounted on the upper edge of the tracks 53 and Il in the path of travel of the roller 5i as the platform travelsupwardly on the rails, said brackets serving to trip the plate so thatit swings downwardly and over the floor.

The plate as is formed as clearly shown in Figs. 9, l0, and 11 of thedrawings, the lower edge being shaped as at 58 to fit over the shaft 33,and a hook extension 29 engages the edge of the plate 55 to swing itdownwardly when the plate 49 is swung up, (see Fig. 10), the spring 53serving to swing the plate upwardly to position shown in broken lines inFig. 9 of the drawings when the elevator is in motion.

The safety brake mechanism B is automatic in operation, and should thecable l-I break or the mechanism jam, the pull on the rollers 31 will bereleased and the spring 45 will pull the links 35 downwardly, asindicated in broken lines in Fig. 6 of the drawings, and this in turnrocks the brake element F on the pin 4! so that the cam-shaped toothedface 44 engages and bites into the upper flange of the side rails, thusholding the platform in this position until the mechanism is repaired,when it again swings to original position.

The equalizing bar E comprises opposed pairs of levers E3 and 6d, theinner ends of which are slidably mounted in the housing 6!, one pair oflevers being slotted as at 62, and these levers are connected by a pin(33 as usual.

The sheaves 23 are mounted on the ends of the levers 59 and E0, andsprings 64 are anchored to each pair of levers and tend to pull themtowards each other, whereas, the cables I-I tend to elongate said leverarrangement.

A switch (not shown) is mounted in the housing GI, and th usual leads 65are connected thereto. A contact 65 is mounted on said housing GI, and apost 61 is mounted between the links 59, a threaded contact 58 being inengagement with the member 66, but if for any reason the links arepulled from each other, the contact will be broken and the current cutofi accordingly. This equalizer mechanism swings as a bridle to suit thecable tension and maintains it constant at all times.

The operation of the elevator is substantially as follows:

When it is desired to elevate merchandise or materials from one fioor toanother, the platform 12 is first loaded, and the motor M is thenenergized to drive the drums D, winding the cables H thereon, anddrawing the platform up the inclined trackways l3 and 14.

When th rollers 5! come into engagement with the bracket 51, the member59 is swung upwardly about the pivot point N and the hook extensions tilengages the inner edge of the extension plate 55, swinging it downwardlyto cover any cracks between the front edge of the platform i2 and thefloor H, and a limit switch L cuts oil the power, the brake C holdingthe platform in this position so that the elevator can be unloaded.

From the foregoing description, it will be understood that I haveperfected a very simple,

practical, and inexpensive stair elevator for elevating merchandise ofall kinds from the floor to floor.

What I claim is:

1. A stairway elevator comprising in combination, spaced-apart railsadapted to be secured to extend the length of a stairway, a platform,rollers carried by the platform and movable in said rails, automaticbraking mechanism connected to the rear rollers of said platform andengageab-le with said rails when applied, links connected to said brakemechanism, flexible lines connected to said links and normally holdingthe brake out of engagement with the rails, drums adjacent the stairwayand on which the lines are l wound, equalizing means interposed betweenthe ends of the rails and the drums and over which the flexible lineslead for equalizing the tension of the individual lines and maintainingthem constant, and means for driving said drums.

2. The combination set forth in claim 1 in which the links arespring-retracted in a direction opposite the upward travel of theelevator, and a slide associated with the braking mechanism for slidingcontact with said rails,

3. The combination defined in claim 1 in which the rollers on the frontend of th platform are grooved to accommodate the flexible lines.

4. The combination defined in claim 1 in which an extension strip isconnected to the front end of the platform, means normally holding saidstrip in raised position, and means for swing ing it horizontally at apoint directly adjacent the upper end of the rails.

5. A stairway elevator comprising in combination, spaced-apart railsmounted over a stairway and extending from one floor to another, aplatform assembly, grooved rollers on the platform and mounted fortravel in said rails, power driven winding drums adjacent the stairwayand flexible cables connected to the platform and windable on saiddrums, a motor connected to the drums, means for equalizing the tensionon said cables, a switch, and mechanically actuated means associatedwith said equalizing means for actuating said switch to open the motorcircuit when the cable pull exceeds a predetermined load.

6. The combination as set forth in claim 5 in which an automatic brakemechanism is associated with the platform, said brake mechanismincluding a cam-shaped toothed member formed with 2. depending leg, saidbrak mechanism being held in retracted position by the cable pull on theplatform, and resilient means also attached to said leg for swinging thetoothed cam member in engagement with the said rail upon cessation ofsaid cable pull.

7. The combination as defined in claim 5in which a normally retractedextension strip is hingedly secured to th front edge of the platform,brackets mounted on the side rails, and trip mechanism mounted on theplatform and engageable with said brackets for swinging said strip tohorizontal position.

8. A stairway elevator comprising in combination, spaced-apart railsadapted tobe secured to extend from one floor to another, a platformassembly having rollers mounted thereon and movable in said rails,standards on the upper floor in alignment with said rails and sheavesmounted on said standards, cables anchored to the standards andconnected to said assembly, winding drums adjacent the rails, a cableequalizing bridle adjacent said standards and through which the cableslead to the winding drums, and a motor for driving said drums.

9. The combination defined in claim 8 in which the equalizing meansincludes a housing, a switch provided thereon, opposed horizontallydisposed links mounted in said housing, one of said links having limitedhorizontal movement with relation to the other, and adapted when fullyextended to open the motor circuit, sheaves on the outer ends of thelinks, and resilient means connecting the opposed links and normallytending to draw them towards each other.

No references cited.

